Improvement is draft-producing apparatus for locomotives



' G. WINGATE. Draft-Producing Apparatus for Locomotives, &c.

UNITED STATES PnfrElvr QEEIGE.,

IMPROVEMENTAN DRAFT-PRDDUCING APPARATUS FOR LOCOMOTIVES, &c'.

Specification forming` pa rt of Letters Patent No. 147,2 141, dated Felcruary 3, 1ST-l; application iled Y November 2l, 1873.

To all lwhom lit may concern:

Beit known that I, GEORGE WINGATE, of Charlestown, Middlesex county and State of Massachusetts, have invented an Improved Draft-Producing pparatus, of which the following is a specification:

The object of my invention is to adapt the draft-producing apparatus 4for which Letters Patent were granted on the 11th day of November, 187 3, to locomotives, steam fire-engines, &c.; and I attain this object by constructing the apparatus in the manner which I will now proceed to describe, reference being had to the accompanying drawing, in which- Figure lis a sectional elevation of the apparatus; Fig. 2, a sectional plan on the line l 2, Fig. l; and Fig. 3, a sectional plan on the line 3 4, Fig. l.

The apparatus has a central passage, a, for the products of combustion, an annular steamchamber, E, at or near its base, an air-chamber, D, an adjustable annular casing, K, communicating-with the air-chamber through a number of openings, and having a large inlet, M, a series of vertical tubes, b, connecting the said air-chamber and an upper chamber, DI, which communicates at the top with the central passage a through a narrow annular opening, f, and a series of steam-pipes, c, which extend from the chamber E into and through the said air-tubes b. In these respects the apparatus is substantially the same as that for which said Letters Patent were granted.

The improved apparatus is intended as a substitute for the ordinary smoke-stack or chimney of alocomotive or steam nre-engine, to the boiler of which it is permanently secured in any suitable manner, the central opening a affordin g a free upward passage for the products of combustion. The whole of the exhaust steam from the engine is conducted through two pipes, h h, into the chamber E, and after lcirculating within the latter passes upward through the pipes e into an annular chamber, E', with which all of the said pipes communicate at their upper ends. The chamber E terminates at the top of the stack in a narrow annular aperture, k, concentric with, and adjacent to, the passage a. The casing K can be so adjustedthat its inlet can face the wind by a worm, m, on a rod, p, which gears into a wormwheel, q, secured to or formed upon the exterior of the said casing K. On a locomotive, the rod p may be contained within or form part of the usual hand-rail which extends along the boiler from the engineers cab to the stack. Ihile the locomotive is in motion, the required blast for the products of combustion through the central passage a is produced and maintained partly by the exhaust steam and partly by forcible currents of air, which enter the casing K through its properlydirected inlet M. The steam, in escaping from the annular aperture L at the top of the stack, produces a partial vacuum immediately over the passage (L, and thus induces a blast, and the air which, in passing from the chamber D through the tubes b, is heated and rarefied both by the steam and products of combustion, escapes, under considerable pressure, through the annular aperture f, into the stack, and thus likewise induces a blast.

It', in running the engine, it be found that the blast is too great, the inlet M of the airchamber can, by manipulating the rod p, be turned partially or altogether away from the wind, which will materially reduce the force of the volume of air admitted, and consequently that of the blast.

The air-blast isespecially valuable in getting up steam, or for maintaining the tire in the furnace in good condition, and the required pressure of steam in the boiler when the locomotive is not in motion, and when consequently there is no exhaust steam for creating a blast. In such case it has been usual to admit live steam from the boiler into the-stack; but with my in vention as good, or even a better, result is obtained without wasting steam, by simplyturning the inlet M of the casing K to the wind, and thus admitting a volume of air, which, in its passage to the upper portion of the stack, is heated and rareiied, and its pressure increased, as before described. Even should there be very little wind, the heating of the air in'its passage through the tubes bwill produce suicient blast to induce a draft for carrying oit' the products of combustion.

I have found that with my improved apparatus a continuous and uniform blast is produced, free from the usual puffs or pulsations, that there is a steady draft from the furnace through the tubes of the boiler, and that the general result is uniformity of steam-pressure und eeonomy of fuel.

I claim as my inventionl. A chimney hzwing a-t the top un opening, 7.', communicating with tu exhaust-steam pipe, und within and below thelmouth it contracted zliperturehf, communicating With a. channel, for the passage of heated zur, substantially its set forth.

2. The combination, substantially as described, of the zur-chambers D and D', und their connecting-tubes b, With the steam-chambers E and E', and their pipes e, extending` through the said :tir-chambers and tubes, all substantially as specified.

GEORGE WINGATE.

fitnesses Y J. H. COTTON, C. YV. QUIMBY. 

